Tone-selective receiver



Nov. 1, 1927.

Filed June 17, 1922 a d/W W w/ w OWQ 1, z w w 3 w 4 m n 6. /m w M W Whll Patented Nova. 1, 1927.

UNITED STAT Jttdfl' E. HALL, OF CHICAGO, ILLINOIS, ASSIGNOR T HALLRESEARCH (70 I C E 0F UHICAGO, ILLINOIS, A CORPORATION 0F DELAWAronn-snnnorrvn nncnrvnn.

a lication and. June 17,

This invention relates to apparatus for receiving communications and hasfor its primary object to permit selected signals only to be receivedwhile all others are ex- 5 eluded.

it. further object of the invention is to provide for a Wide range 0tselection in signals and the accurate exclusion of all encept theparticular signal selected. it further object of the invention is topermit the selection of any particular tone from a number that may bepresent so that com vrmmication may be carried on with that tone withoutinteri'erence from or with other tones.

Further objects of the invention will become apparent as the descriptionis read in connection with the accompanying drawings, in which sign. 1is a diagrammatic view showing one embodiment of the invention; and

'onal opening 13 receiving a similarly d plug 1d having a threadedsocket 15 i ceive a screw it having a head 17 worlring against thewasher 18.. The free end of the plug 13 is connected with a strongspring 19 which in turn is connected with the string ill. The adjustableconnection is used to tune the receiver by adjusting the tension of thestrin and" the spring is desirable to permit v1 rations lengthwise tothe string while maintaining the tension thereon.

' lln this device the signals are received by a telephone magnet 20which operates a reed 21 having one end attached to the string 10 at 22and the other end suitably fixed to a support at 23. The currents set upby the incoming signal s will causethe magnet to operate the reed inmuch the same manner that the ordinary telephone diaphragm is prior art.

. it is a modified form oi the invention.

Li have shownthis support 12 with ,varies according 1922. Serial No.568,939.

operated and the vibrations will have a tone corresponding to the toneof the signal. I have used the term reed to describe an instrument thatwill vibrate after the man nor of the reed in musical instruments, butto i do not intend to be limited in this or any respect except as madenecessary by the The invention the be applied to anything that willmalre vibrations corresponding to alternating or pulsating can rents.

The string 10 is biased to one sideby a rod 24 connected tothe middle ofthe string one end and at the other end with a spring 25 which in turnis connected with an to justable plug 26 carried by a suitable support2?. The plug 26 is mounted similar the plug 13 so that the bias of thestring may be adjusted to suit particular conditions The spring 25 isrelatively light so as to to permit the string 16 to vibratetransversely with comparative freedom but prevents it from becominstraight thus not vibrating freely. rod 28 is connected to the string atthe same point as the rod 241- and carries float 29'resting on the smalldie phragm 30 in a stethoscope 3]. having an ear piece 32 at the endopposite the phra m. The rod 28 may be connected the diaphragm in anyother suitable ner so as to communicate the transverse vibrations of thestring thereto. The stethoscope is used in this illustration merely asan example and it will be clear other suitable receiver be used in its Wplace. v

When a signal is received by the magnet 20, the reed will be vibratedand by vary ing the tension on the sprin will have a tendency toalternately lower t e point 33 i -l the spring" and permit it to beraised. When the period of the signal corresponds to period of thestring, the cumulative action of the reed will cause the comparativelyWide transverse vibrations of the string.

Inasmuch as the frequency of the string to the tension, length and mass,av-ery wlde range of periods can be given to the string by changingthese factors. Consequently,a device of this kind can be 11% inadeadjustable to suit a very great range of tones used in signaling.

The string can be .tunedby adjusting either or both of theiplugs 13 and26 to give any tone within the range of its length no reception instring,

and mass. Diiferent lengths and different masses can be used to give theinstruments diiierent ranges and by a suitable selection the instrumentscan be made to equip a line of communication so that a great variety ofsi aling tones can be used simultaneously w ile each instrument can betuned to receive only selected tones within its particular range. Theseossibihties of the invention make it particularly adaptable to use inmultiplex telegraphy and in radio which there is ordinarily interference, and those skilled in the art will readily find other uses forit.

In Fi 2, I have shown a modified form in whic a string 35 is stretchedbetween fixed supports 36 and 37 and made'adjustable by a plug 38similar to that shown at 13.. However, in this form I have madeprovision for using two segments 39 and 40 of the string operated by asingle reed 41, the se ents being biased in opposite directions yadjustable plugs a2 and 43 operating through springs 44 and 45 and rods4.6 and 47 corresponding to the similar parts in Fig. 1. The right endof the segment 39 is determined by a point of connection with a rocker48 having relatively great mass, which rocker is preferably located onthe opposite side of the spring 49 from the lug 38. This sort of an aparatus is more highly selective than that s own in Fig; 1 and is ivenmerely to indicate how those skilled in the art will readily modify thehysical form to suit conditions to be met 1n practice.

In both these forms I have shown the stringbiased by a rod connectedwith the string, but it will be understood that in some instrumentsgravity will give the wire suflicient bias to produce the necessaryresults and in other'instru nents various other suitable means may .beresorted to.

I am aware thatchanges may be made in the form, construction andarrangement of the invention, as set forth in the selected embodimentherein, without departing from the scope or sacrificing any of itsmaterial advanta es, and I therefore reserve the right to ma e all suchchanges as fairly fall within the scope of the following claims.

I claim:

1. A tone selective receiver comprising a string, said strin beingstretched between two sup orts an fixedly held at one end, means oradjusting the tension on said means for causing transverse vibrations ofsaid string, and signal receivin means connected to said string andoperate by said vibrations.

' 2. A tone selectivereceiver comprising a string, said strin beingstretched between two sup orts an fixedly held at one end means oradjusting the tension on said string, means for transforming variationsin an electric current into transverse vibrations of said string, andsignal IBCBIVIDO' means vibrations.

3. A tone selective receiver comprising a string, said string beingstretched between two supports and fixedly held at one end, means foradjusting the tension on said string, means for causing transversevibrations of said string, signal receiving means connected to saidstring and operated by said vibrations, and means to bias said string atthe point of its connection to said receiving means.

4. A tone selective receiver comprising a string, said string being.stretched between two supports and fixedly held at one end means foradjusting the tension on said string, means for transforming variationsin an electric current into transverse vibrations of said string, signalreceiving means connected to said string and operated by saidvibrations, and means to bias said string at the point of its connectionto said receiving means.

5. A tone selective receiver comprising a string, said strin beinstretched between two sup orts an fixed y held at one end, means oradjusting the tension on said string, means for causing variations inthe tension of said string, said variations resulting in transversevibrations thereof, and signal receiving means operated by saidvibrations.

6. A tone selective receiver com rising a string, said strin beingstretche between two supports an fixedly held at one end means foradjusting the tension on said string, means for causing variations inthe tension of said string by variations in an electric current, saidvariations in tension causing transverse vibrations, and signalreceiving means operated by said vibrations.

7. A tone selective receiver comprising a string, said string beingstretched between two sup orts and fixedly held at one end means oradjusting the tension on sai string, means for causing variations in thetension of said strin ,said variations resulting in transverse virations thereof, signal receiving means operated by said vibrations andmeans to bias said string at the point 0 its connection with saidreceiving means.

8. A tone selective receiver comprising a string, said string beingstretched between two supports, means for adjustin the tension on saidstring, means for causing variations in the tension of said string byvariations in an electric current, said variations in tension causingtransverse vibrations, signal receiving means operated by saidvibrations and means to bias said string at the point oi its connectionwith said receiving means.

.9. A tone selective receiver com rising a string, said string beingstretche between connected to said string and operated by said Ill twosupports, means for adjusting the tension on said string, means forcausing variations in the tension of said string, said variationsresulting in transverse vibrations thereof, signal receiving meansoperated by said vibrations, means to bias said string at the point ofits ing means, and means to adjust said last named means.

10. A tone selective receiver comprising a string, said string beingstretched between two supports, means for adjusting the tension on saidstring, means for causing variations in the tension of said string byvariaconneetion with said receiv-' tions in an electric current, saidvariations in tension causing transverse vibrations, signal receivingmeans operated by said vibrations, means to bias said string at thepoint of its connection with said receiving means, and means to adjustsaid last named means. 11. The combination of a string, means forputting the string under tension, yielding means to bias the stringbetween its ends, a reed connected with the string, a magnet forvibrating the reed and a stethoscope connected with the string at thebias.

RAY E. HALL.

